Background and objectives Epidural analgesia is the gold standard for post-thoracotomy pain management and can be started before or after surgical incision. This systematic review and meta-analysis investigated whether pre-emptive epidural analgesia before thoracotomy incision reduces acute and chronic post-thoracotomy pain in adults compared with epidural analgesia after incision.

Methods We searched databases including MEDLINE, Embase, and CENTRAL for randomized controlled trials comparing epidural analgesia initiated before (pre-emptive group) and after (control group) thoracotomy incision in adults. The primary outcomes were the pain intensity during rest and coughing within 72 hours after surgery and the incidence of pain 1 to 6 months after surgery. Data were combined with random-effects meta-analyses. We rated the quality of evidence as high, moderate, low, and very low using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) method.

Results We included 19 trials with 1062 participants involving 529 in the pre-emptive group and 533 in the control group. The pain intensity was significantly lower at rest within 72 hours after surgery (19 studies, n=1062) and during coughing within 48 hours after surgery (11 studies, n=638), and the incidence of pain was significantly lower 1 to 6 months after surgery (6 studies, n=276) in the pre-emptive group than in the control group. The quality of evidence was moderate or low in the primary outcomes.

Conclusions Our review provides low-quality evidence that pre-emptive epidural analgesia reduces the intensity of acute pain and the incidence of chronic pain after thoracotomy in adults.

Protocol registration number CRD42019131620.